The present invention relates to improved means for supporting equipment which is subjected to relatively high temperature differentials which cause both vertical and horizontal expansions. More particularly, the invention relates to such improved support means when used in connection with equipment such as a cyclone separator stage, which forms part of a burner vessel employed in fluid coking.
A conventional way of supporting cyclones is to support them from the vessel head by rods and from the plenum chamber by the outlet ducts. The plenum chamber comprises a cylindrical skirt welded to the vessel head and is enclosed at the bottom by a dished floor member welded to the lower edge of the skirt. According to this arrangement, some of the cyclones are supported from the vessel head and some from the plenum chamber floor. The problem with such arrangements is that the support system is subjected to different temperatures which causes thermal expansion problems. Other known designs support all of the cyclones from the plenum chamber by means of rods and cyclone outlet ducts and this type support system avoids the problem of differential thermal expansion. In these conventional cyclone systems, the plenum chamber floors are generally fairly thick, for example, on the order of one inch or more, and are constructed to carry the weight and differential pressure loads of the cyclones during operation of the vessel. The need for this heavy construction is due to the load imposed on the floor by the cyclones which introduce compound stresses, i.e. primary bending and tensile stresses in the plenum floor and cylindrical support skirt.
Other prior art arrangements for supporting cyclone separators are shown in U.S. Pat. No. 3,951,629 wherein a support beam secured to the vessel head by support bars actually supports the cyclone separators. This patent also discloses the expedient providing a thinner floor (see Column 4, lines 50-53); however, the support rods or bars do not directly support the operator stages and there is no floor supported by the rods. U.S. Pat. No. 3,982,902 discloses a support for cyclone separators which employs a horizontal bar that is pivotally mounted to the vessel wall. U.S. Pat. No. 2,873,175 discloses a cyclone supported from the vessel head (see Column 7, lines 31-35); however, there is no plenum chamber disclosed in the patent. Still yet another support scheme for cyclones is disclosed in U.S. Pat. No. 2,439,850 wherein the cyclones are attached to each other such that they move as a unit.
None of the prior art, however, is considered to afford the advantages of a cyclone support system wherein the plenum chamber is constructed and arranged to accommodate thermal expansion and wherein the plenum chamber serves to separate and contain the relatively clean gas generated from the dilute phases produced in the vessel and does not support the cyclones; but instead the cyclones are supported by individual support means connected directly to the head of the vessel and the plenum chamber floor in turn is supported by the cyclones.